Power clamps are known in the art for mounting on a base, with a clamp arm actuated by air or hydraulic cylinder through a toggle linkage which reaches a fixed clamping position when three pivot points of the linkage reach a straight line or slightly overcenter position.
Power clamps aare also known which employ a roller and cam principle where a pivoted clamp arm having an integral roller track is actuated by a straight line piston having reaction rollers confined to a straight line reaction track.
U.S. Pat. No. 4,576,367 discloses a power clamp having a pivoted arm with cam track engaged by a roller on a pivoted link actuated by toggle linkage through a straight line power piston. Several toggle links are involved in addition to the pivoted link defining the circular arc travel of the roller.